Add periods to the end of each description

For consistency

doc/development/snowplow.md

@@ -311,9 +311,9 @@ Custom event tracking and instrumentation can be added by directly calling the `
 | `property` | String                    | nil           | As described in [Structured event taxonomy](#structured-event-taxonomy).                                                          |
 | `value`    | Numeric                   | nil           | As described in [Structured event taxonomy](#structured-event-taxonomy).                                                          |
 | `context`  | Array\[SelfDescribingJSON\] | nil           | An array of custom contexts to send with this event. Most events should not have any custom contexts.                             |
-| `project`  | Project                   | nil           | The project associated with the event |
-| `user`     | User                      | nil           | The user associated with the event |
-| `namespace` | Namespace                | nil           | The namespace associated with the event |
+| `project`  | Project                   | nil           | The project associated with the event. |
+| `user`     | User                      | nil           | The user associated with the event. |
+| `namespace` | Namespace                | nil           | The namespace associated with the event. |
 
 Tracking can be viewed as either tracking user behavior, or can be used for instrumentation to monitor and visualize performance over time in an area or aspect of code.